If we replaced all of our freeways with solar panels could it power all of the United States?

Answers

That depends, are we including the added power costs that would be created by losing efficient means of overland transportation?

More seriously, it was calculated that a square of solarpanels that’s about 92 miles on each side (or about 8500 square miles) could theoretically provide enough power to supply the entire United States (though whether or not this is true in practice remains to be seen.)

In any case, there are about 94,000 square kilometers of highway in the US. Convert that to miles and you get about 58,000 square miles, which according the the article I’ve cited would be more than enough. Interestingly, it would actually be enough to cover about 1/5 of the world’s total required energy supply, according the other citation.